The present invention relates to a composition of polyarylene thioether (hereinafter referred to as PATE) having a high crystallization rate and forming a minute spherulite structure.
More in detail, the present invention relates to (1) a composition of PATE having a high crystallization rate and being prepared by combining 0.001 to 10 parts by weight of kaoline of a mean particle diameter of 0.03 to 2 .mu.m with 100 parts by weight of PATE having the repeating unit of ##STR2## as the main constituent and (2) a composition of PATE prepared by further combining an inorganic filler and/or a fibrous filler with the composition of PATE of (1).
PATE is a resin developed as a heat-resistant, chemical-resistant and flame-resistant thermoplastic resin. Particularly, since PATE is crystalline, PATE can be melt processed such as injection molding, extrusion molding and has a characteristic points that molded products obtained from PATE are excellent in physical properties such as dimensional stability, strength, hardness, insulating property.
Taking advantage of these characteristic points, PATE is used in the fields of electricity, electronics, cars, aeroplanes, precision machinery and chemical engineering, etc.
However, the conventional PATE has a defect that its crystallization rate is low and accordingly often results to have coarse spherulites.
Because of the above defect, when PATE is fabricated, for example, with injection molding, there has been a problem which lead to practical physical defects such as long molding cycle, many occurrence of flashes and low mechanical properties of molded products.
To improve the defect, use of a nucleating agent can be considered, however, there is not such agent, according to our knowledge, that is effective to all crystalline polymers and there has certainly been no such agent effective for PATE.
As a result of the present inventors' extensive studies for a nucleating agent effective to PATE, it has been found out that kaoline gives an excellent effect to PATE as the agent, namely, has the effect of improving the crystallization rate and of micronizing the spherulites.
The present invention has been completed based on the finding.